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Re-installing upper drive question

M

montanamountan

New member
First, I have to confess that this is my first venture with working on a boat - but you have to start sometime, right....?....

With that: I have a '75 Mercruiser 140HP, and I just finished tearing apart the lower and upper drive to replace the water pump, water pocket assembly and exhaust bellow (bellow over the u-joint still okay); but now that I'm putting the upper drive back, I can get everything to slide together (by hand) except for the last 3/16 - 1/4 inch. Figuring this was the spline just getting a little tight - I began tightening the nuts very slowly (alternating side to side) to see if it would move without a lot of effort; and with each twist, things went okay until the upper drive assembly was tight against the housing.

That said, while researching other topics, I've seen several references that say the drive should slide all the way without forcing, so I just want to be sure that I used a reasonable approach and didn't "cross" anything before I move forward with putting the lower drive on.
 
first thing is to make sure that the shift shaft is turned clockwise all the way and the prop/shaft is turned c'clockwise until locked in FORWARD.

Second make sure the copper tube is inserted propperly into the upper case plastc water jacket cover.

third, your vertical shaft (drive shaft) has a preload pin in the top just above the splines, correct? If so when the two halfs come together the pin will keep them apart.

fourth, the Bronze shift arm in the upper must be facing 12:00 straight forward and as the top case slides onto the bottom case the bronze shift arm MUST engage the shift shaft while the shift shaft is MAINTAINED fully clockwise and the prop/shaft (counterclockwise) is locked (lightly) in forward to keep pressure on the shift shaft. Failure to do this will cause the shifting to be wrong when done.

next if all the previuos stars have aligned and you get the upper down close to the lower ( and of course you have double checked for the oil passage oring is still in place (about 1/4 inch diameter between the two cases)

Now put the two side nuts on and tighten them to draw the two cases together.

The spring loaded pin will keep them apart and will need to be compressed with the nuts. When tightening the two side nuts the cases SHOULD tighten down with very little effort, just enough to overcome the spring pin.

THis answer your question?
 
Did I miss understand what he was assembling??????? He was not clear on what he was assembling, the two halfs or the drive to the gimbal housing!!!!

ME BAD

If the "outdrive" will not tighten to the "gimbal housing"

two things.

1. as said the alignment may be out but if it came out with ease unlikely the alignment!!!

2. the bronze shift arm must be pointing at 12:00 and the outdrive in forward (turn bronze arm clockwise while truning prop counterclockwise and the shift hand control also must be in forward also.

one other issue is to make sure the shift linkage inside the gimbal housing is greased up well and the bell crank is inside the shift arm (cable end).

If you installed new orings on the input shaft they can cause a bit of resistance, make sure you grease the crap out of the splines and orings..........
 
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It's a lot easier to reinstall the leg if you put it back on in one piece. I'm not sure how you'd turn the drive to align the splines if you haven't got a prop to turn to help you.
Also, just because the drive came off, is no guarantee that the alignments good.
It sounds to me like the shift arms were not aligned to make the last inch that hard to install. They shouldn't have to be forced on.
 
ever hear of the merc kick. It's well known among my friends here, it's a very specialized kick, different from the kick in the butt used for cheating wives,stray dogs and kids.
 
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